Airplane pickup mechanism



Aug. 28, 1945.

J. X. PHILLIPS AIRPLANE PICK-UP MECHANISM 2 Sheets-Sheet 1 Filed June 22; 1942 m H M JOHN/If PAULA/R5 Aug. 28, 1945. J. x. PHILLIPS AIRPLANE PICK-UP MECHANISM Filed June 22, 1942 2 Sheets-Sheet 2 Patented Aug. 28, 1945 AIRPLANE PICKUP MECHANISM John X. Phillips, Vienna, Va., assignor to G. Tucker Smith and E. Govan Hill, bothof Richmond, Va., trustees Application June 22, 1942, ser ia1 No. 448,009

16 Claims. (Cl. 2581.6)

. This invention relates to airplane pick-up mechanisms and more particularly to a mechanism of the type wherein a catapult is employed for projecting the load to be picked up, upon the engagement of an airplane-carried hook with a loop connected to the load.

Several airplane pick-up mechanisms have been developed which arehighly efiicientin operation for permitting an airplane, without landing, to engage a loop connected to the load to be picked up and in so doing to release a catapult mechanism which projects the load approximately at the speed or flight of the airplane tov permit the plane to support and carry the load without any transmission of substantial shock to the plane. These mechanisms are of various specific types and employ a latch which holds the catapult carriage in fixed position; a source of power tending to project thecarriage, a pair of spaced masts; and a loop supported by the masts and connected to the article or load on the carriage, means being provided whereby initial engagement of they loop by an airplane-carried hook releases the latch and thus permitsthe source of power to project the carriage. Devices of this character have been highly successfully operatedon numerous occasions. The degree of force exerted on the carrier tending to project it is governed by two factors, namely, the weight of the load and the speed of the airplane which is to pick up the load. Generally speaking, one of these factors ordinarily is considered to be a constant, namely, the speed of the plane, since it is the commonpractice for the pick-up plane to be flown at an air speed of approximately 100 miles per hour at the time the pick-up operation is performed.

Actually, the speed of the plane cannot be considered to be a constant inasmuch as there is sometimes substantial dillerence between the air speed and the ground speed of an airplane due to wind velocity, as is Well known. Therefore, the

operator of a mechanismlof this character may increase or decrease the projecting power to compensate for variations in wind speed but the force exerted is varied only according to the judgement of the operator and thus is extremely inaccurate. This inaccuracy is of no consequence when picking up relatively light loads but progressively becomes a more serious consideration as attempts are made to pick up progressively heavier loads.

An important object of the present invention is to provide a novel mechanism for automat cally determining the force applied by the source of power to tend to move the catapult in accordance with variations in wind velocities, thus far more accurately discharging the article at a speed equal to that of the land speed'of the airplane.

A further objectis to provide means whereby the apparatus may be initially set accordingto the load to be projected and which initial setting will be automatically changed in accordance with I variations in the velocity of the wind whereby the article. to be picked up will be discharged at a proper speed taking into consideration both the weight of the article and the ,land speed of the airplane.

A further, object is toprovide a novel apparatus of the character referred to which is particularly adaptable for use with a tensioned shock cord device employed as the means for projecting the catapult carriage. v v

A further object is to provide a mechanism of the character just referred to wherein a Windlass is employed for tensioning the shock cord employed for projecting the catapult carriage, and wherein automatic means operates to wind or unwind the windlass to vary the tensioning of the shock cord device in accordance with variations in the wind velocity.

Other objects and advantages of the invention will become apparent during the course of the following description. v

In the drawings I have shown one embodiment of my invention. In this showing- Figure 1 is a side elevation of the apparatus showing a plane flying thereover and about to engage the pick-up loop,

Figure 2 is a front elevation of the apparatus,

Figure 3 ,isan enlarged side elevation of parts of the catapult mechanism-most of the catapult vehicle being omitted,

Figure 4 is a detailed sectional view on line 4-4 of Figure 3, and,

Figure 5 is a diagram of the Wiring system used in conjunction with the apparatus. v Y

Referring to Figure 1 the numeral 50 designates an airplane of any desired type below which is suspended an arm I I having a pick-up hook I 2 at its lower end engageable with the pick up loop, to be referred to later. The arm H may be p v cted as at IE to the bottom of the fuselage of the plane to be swung upwardly to inoperative position upon the upward pulling of a cable M. The hook l2 may be carried by a cable (not shown) housed in the arm I l whereby itmay be pulled upwardly toward the bottom of the plane which is provided with a door (not shown) through which the article may be pulled into the plane after having been picked up. The portions of the pick-up mechanism associated with the plane form no part per se of the present invention and need not be illustrated in detail.

The apparatus forming the subject matter of the present invention comprises a vehicle l5 supported at one end by wheels l6 and at its opposite end by a caster wheel I! provided with a draft connection l8 whereby the apparatus may be pulled to any desired spot on the pick-up field and turned in any-direction in accordance with the direction of the wind. .The vehicle '5 may be of any suitable construction and forms per so no part of the present invention. The vehicle is is provided with a relatively heavy transverse.

structural element 2| (Figure 3) for a purpose to be described.

A catapult carriage 22 is supported formovement in the vehicle l5 by any suitable form of I trackway means generally indicated by the numeral 23 in Figure 1. The particular form of I carriage and the trackway supporting means therefor is of no importance in connection with maximum strain on the yoke 51 occurs horizonthe present invention. The carriage 22 is provided'with a detent 24 (Figures 'zfanu 3) engage able by a hook 25 carried by a lever 26 pivotally connected to a. bracketZl. This latch isreleasable by any suitable means (not shown) upon the engagement by the hook I2 with a pick-up 20 loop 28, for example, by the means shown and described'in theprior patent to Jeannot G. In-

gres and Henry W. Hey, No. 2,356,671, issued August 22, 1944. The loop 28 has a horizontal portion 29 adapted to be supported by clips 39- arranged at the upper ends of masts 3| and the loop further comprises downwardly and rear. wardly. converging portions 32 connected at their rearends tolan article 33 arranged in the carriage .22... The clips may be electrical switch elements: movable into. contact with each other upon the pulling of the loop portion 29 by the hook l2 to close a circuit through a solenoid to operate the lever 26 and release the hook 25 from the detent 24, as fully disclosed in the prior patent referred to. The masts 3| may be of any suitable type and may be supported at their lower ends by mushroom bases 34. Rods connected to the masts may operate in sockets 35 pivoted as at 31' with respect to the vehicle 15 to be swung to inoperative positions adjacent and parallel to the sides of the vehicle when the apparatus is not in use. Under the latter condition, the masts will be disconnected from the bases 34 and arms 35 and laid on the top of the vehicle whereby the apparatus as a whole occupies minimum space for transportation.

' The carriage 22 is provided with a depending. structure 38 to which one end of a shock cord device 39 is connected. Any number of shock cords may be employed dependingupon the maximum load to be projected by,the catapult,-

and asis well known, the shock cord is formed of a substantial number of rubber threads housed within an extensible fabric casing. The other end of the shock'cord device is secured toa connection 40 which, in turn, .is-connected to one end of a flexible belt ll passing around a pulley 42. The other end of the belt H is wound about the drum of a spool 43 (Figure 3) forming part of a Windlass mechanism for elongating the shock cord device 39. The spool or drum .43

carries a gear meshing with a worm 45 car-' as will become apparent, accordingly the drum 43 may be turnedin either direction to wind or unwind the belt 41 with respect thereto.

by-and suitably insulated from the plate I l The pulley 42 carries stub shafits 54 and 55 at its respective ends (Figure-4) and these shafts are mounted in the arms 55 ofa yoke 51 which carries a shaft '58 centrally. thereof (Figure 3).

5 The shaft 58 extends through a bearing 59 carried by one end of a cylinder Bil in which is arranged a piston Bl drilled to provide a leakage port 62. A relatively heavy coil spring 63 urges the piston 6! to the left as viewed in Figure 3. 10 ,The cylinder Bilis carried by a bracket 54 secured to :the frame member 2!. It will be apparent that the shafts 54 and 55 are wholly supported tally, and this strain is adequately taken up by the supporting means referred to. It will be apparent that as the belt 4! is wound on the drum 43 the pulley 42 is pulledto'the right as viewed in Figure 3 against the relatively heavy tension of the spring 63.

Referring to Figure 4 it will be noted that the shaft 55 projects through a slot 65 in one of the plates 23, this slot being sufficiently longto take care of maximum horizontal movement of the shaft 55. under various conditions to be described. Theouter end of the shaft 55 is engageable by a fork 65 formed at the lower end of a lever 6'! provided at its upper end with an arcuate por- 30 tion 68 having an arcuate slot 69 therein. A

bolt Ill projects through the slot 89 and through a plate ll formed as shown in Figure 3 and pivotally connected as at 12 to the lever 61. Upon the loosening of the bolt 10 theplate ,l I may be turned about the axis of; the pivot 12 and seconnected to the vehicle 15. The pivot element.

12 may be conveniently supported by a bracket arm 15' carried by the bracket 15 (Figure 4). The lever 13 is provided with a depending arm 16 (Figure 4) and the lower end of this arm carries a pair of contacts 11 and 18 respectively, suitably insulated from the arm 16 and engageable with elements 19 and respectively, carried One of the elements 19 and 80 is an elongated contact and the other is a rheostat element, and these elements are duplicated at opposite sides of the. vertical center of the plate H as will be described 5*, in connection with Figure 5. Therefore, it may be assumed that the numeral 19 designates a pair of elongated contacts and that the numeral 80 designates a pair of rheostat coils.

The lever 13 has connected thereto oppositely 66 extending tension springs BI and 82 each of which is carried by'the upper end of a post 83 and the lower ends of. theseposts may be supported by a laterally extending arm 84 carried by a portion of the vehicle as shown in Figure 4. The bracket W215 may be supported by. the same element if desired. It will be apparent that the springs 8| and 82 tend to maintain the lever in a central neutral-position as shown in Figure 3, in which case the switch contacts I1 and 80 will be ar- 7 ranged between and slightly out of contact with all of the elements 19 and 80.

The lever 13 is provided at its upper end with an element adapted to ofier resistance to the wind and shown in the present instance as adisk- 85; 75 It will be apparent that wind pressure against-,1

contact II 4 and rheostat coil III.

either side of the disk 85 will tend to move the lever I3. An arm 86 (Figure 3) carried by the lever I3 is provided with a slot 81 in which is arranged a pin 88 carried by the upper end of a rod 89, This rod extends through a bearing 90 formed in one head of a cylinder I in which is arranged a piston ,IOI connected to the lower end of the rod 89 and drilled to provide a leakage port I02.

The motor 52 may be controlled by the electrical system shown in Figure 5. The motor comprises an armature I03 and a field I04 and current is supplied to the motor by line wires I and I06 shown diagrammatically as being connected to the armature I03. The wire I05 is shown as having a switch I08 therein which is engageable by some part of the carriage 22 when the latter is in latch'ed position to engage a contact I01 connected by a wire I08 to the contact I 09 of a manua1 switch IIO. Branch wire I II and I I2 extend from the respective wires I05 and I06 and these wires, in turn, are respectively connected to elongated contacts H3 and I I4 which are the pair of contacts constituting the element I9 as indicated in Figure 4. Wires H5 and I I6 lead respectively from the wires III and H2 to rheostat coils II! and H8 which constitute the elements 80 as shown in Figure 4. The switch elements I1 and I8 are normally arranged in the neutral position shown in Figure 5 and are moved in one direction by the lever I3 to respectively engage the contact II 3 and rheostat coil H8, or in the opposite direction to respectively engage the The switch elements 11 and I8 are connected to the respective ends of the motor field I04 by wires I I9 and I20.

The electrical system, of course, is provided with control means for releasing the tension of the shock cords 39 to reset the carriage 22 with the latch 24 engaging the lever hook 25, and to then manually operate the motor 52 to provide a normal tensioning of the shock cords. A double wire I and has its second wire I23 connected to the wire H2. The switch I2I i movable into en-- gagement with contacts I25 and I28 the latter of which is connected by a wire I27 to the wire I I 9. The contact I25 is connected by a wire I 28 to the wire I I I. Accordingly, when the switch I2I is closed this switch, and the wires I23 and I2! connect the wire II9 to the wire II2 while the wires I22 and I28 connect the wires III and I20, independently of the switch elements 11. It will become apparent that the parts of the switch controlled by the deflectible member 85, when the switch I2I is closed, will be set to unwind rath'er than to wind the Windlass drum I43, and accordingly the wires I I9 and I20'are provided with cutclips at-the upper ends of the masts. Theset screw I0 will have been loosenedand the plate' I0 turnedon its pivot I2 to set it with respect to the lever. 61 according to the load to be picked up, as will become more apparent later.

Assuming that no wind is blowing the levers 61 and i3 will stand vertically as shown in solid linesfin Figure 3. Under suchconditions the oif switches I29 and I30 which are opened prior to theclosing of the switch I 2I. The switch'es I29 and I30 have been shown as separate single throw switches for simplicity of illustration in the closing of the switch I2-I will open the switches I29 and I30 and vice versa.

The operation of the apparatus is as follows:

It will be assumed that the apparatus is set with the shock cords 39 tensioned and with the care riage 29 latched in inoperative position ready to project the article 33 to be picked up by the plane. The loop 28 will have its horizontal portion 29 extending across and supported by the drum 43.

contact elements 11 and I8 will occupy the neutral positions shown in Figure 5'out of engagement with both contact strips I I3 and I I4 and both rheostat coils -I I! and I I8. In Figure 3 the arrow pointing, toward the disk indicates a possible wind, it being, apparent that the plane approaches from the right as shown in Figure 1. Assuming that the plane will approach at an air speed of 100 miles per hour and a head wind of 10 miles an hour starts to blow, the plane will approach atv a land speed of miles per hour. Thecatapult therefore will have been set to pro-' ject the article at a speed of 10 miles per hour in excess of theland speed of the plane and will thus overshoot theplane when the pick-up operation is performed.

Assuming that ,a'head wind is blowing the anemometerdisk 85 will be moved to the right as viewed in Figure 3, for example, to the dotted line position-shown in such figure. This operation turns the lever I3 about its pivot I4 and moves the contacts I1 and I8 respectively into engagement with the contact strip H4 and rheostat I I1. All of the switches I06, IIO, I29 and I30 will be closed undersuch conditions, as will become apparent, and the motor 52 will be energized to cause its worm 5| to drive the worm wheel 50 and thus rotate the windlass drum 43 through the worm 45 and worm wheel 44. The Windlass drum will be rotated in a counterclockwise direction in Figure 3, thus unwinding the belt M from the This operation relieves the tension of the shock cords 39 whereupon their tension will be overbalanced by the heavy spring 63 (Figure 3) tomove the piston 6| toward the left and impart similar movement to the pulley 42 and consequently to the shafts 54 and 55 of this'pulley. The shaft 55, engaging the fork 66 (Figure 3 and 4) will move the lower end of the lever 81 toward the left to movethe plate II above the pivot I2 to the'right. This obviously reverses relative movement of the contacts 11 and 18 with respect to the contact strip H4 and rheostat ill, the latter continuing to move until the neutral relative positions of the parts is restored. As

soon as the contact strip I I4 and rheostat III move out of engagement with the respective switch contacts 11 and I8, the motor 52 will be deenergized to stop the unwinding of the belt M and the apparatus will be so designed that the reduced tension of the shock cords 39 will provide the required force for projecting the article 33 at the land speed of the airplane when the latter passes over the apparatus.

Assuming that just prior to the approach of the airplane the wind will have been blowing in the opposite direction, it will be a tail wind with respect to the airplane increasing its land speed. For example, if the air speed of the airplane is miles per hour and the tail wind is blowing at 10 miles per hour, the land speed of the plane as it passes over the apparatus will be miles operation will occur with the article travelling 10 miles per hour slower than the land speed of the plane, and this difference in speed can be a serious matter ifa substantial weight is to be picked up as willbe apparent.

-With the present apparatus a tail, wind will move the disk 85 and lever 13' to the left of the 63 isincreasingl yloaded. This operation movesthe portion of the plate H above the pivot I2 to theleft in Figure 3 untilthe contact strip H3 and rheostat H8 are disengaged? from the respective switch contacts 11 and 18 The motor 52 will vth'en stop-with the shock cords 39 properly tensioned to project the article 33 at the increased speed called for in accordance with what will be the land speed of the plane when 'it approaches.

Assuming thatthe plane 'n'ow f'approach'es" for the pick-up operation, it will'be flown over the apparatuses shown in Figure 1 and the engage-' ment of the'hook lzrwith the horizontalportion 29 of the loop28 will pull the loop from the fingers 30 and this'operationefiects the swinging of the lever 26 to release the =latchel'ements'24- and =25.'

This operation and .the parts required therefor formno part ofthe present invention per se and may be of any desired type. For example, the releasing of the catapult may be effected by the electrical release mechanism shown and described in the patent of J cannot G. Ingres an'dHenry W. Hey, No. 2,356,671, dated August 22, 1944. Upon the releasing of the latch mechanism the catapult will project the load, acceleration ofthe carriage and the article taking place very rapidly and the article leaving the carriage at a speed closely approximating that of the plane to'prevent the transmission of any shock :loads thereto.

vThe sudden reduction in the tension of the shock cords incident to the-projecting of the article will permit the spring 63to project the piston 6|; toward the left'as viewed in Figure 3.

The pistonB-l, with itsbleed opening 62, mounted in thecylinder 68 provides a dashpot action to cushion movement'of the piston 6|. Movement;

of this piston to theleft will take place without material shock, therefore, but its movement will turn the lever 61 and this operation will tend to close circuits by energizing the-motor 52. operation is undesirable, of course, and accord ingly-the switch N16 is provided for preventing energization of the motorgthis switch being'held in closed position by the carriage when the latter is latched in the position shown in Figure 1.'

Upon the releasing of the catapult, therefore, the motor circuit will be opened at thecontact I01 and accordingly the=motor will not operate upon the releasing of the catapult.

Thepartsof the motor and Windlass will remain in the same positions as when the shock c'ords 39 were tensioned with the apparatus set for operation and in order to reset the apparatus it is necessary to unwind the belt. M from the Windlass drum-43 to tpermit the carriage 22 to be moved to latched position. The movement This I of the piston'Bl to the left (Figure 3) will have turned the plate H to engage the switch under contacts ll and 1-8 with the strip H3-andrheostat 1 l8, which positionotthe: switch elements corresponds to the operation which 'oc'c'urswhen a 'tail wind is blowing, as previously described. If the'circuit thus provided were permitted to control the motor 52, the latter would-operate to turn the Windlass drum 33 in a' clockwise direction (Figure 3) to tend toincrease the tension of the shock cords 39. For the resetting of the apparatus it is therefore necessary to 'prevent such controlling of the motor 52. In order to reset the carriageQtherefQre; the operator will open the switches I29 and I3U'and close the switch |2l.' It will'be-assumed that the 'main' control switch H0 will have remained closed, and it therefore will be necessary for the operator only to hold the switch I06 in closed position to efiect energizatlon of the motor 52. The circuit for the field I04 provided by theswitch I 2| corresponds to the circuitprovided'whe'n the switch contacts 11 and i8 enga'ge'the contact strip H4 and rheostat H1. Thus the Windlass drum 43 will turn in a counterclockwise direc tion (Figure 3) to unwind the belt 4|. Thisoperation is continued until the carriage 22 can be manually moved to latched position. 1

It will be apparent that when tension is'-re lieved in the shock cords 39' to a suflicient eX-' tent to permit resetting of the carriageZZ, the

piston 6| will be approximately at the left hand end of the cylinder 60 (Figure 1) and the lever 61 and plate ll thus will be moved to such a position with respect to the lever 13 that the switch contacts I! and 18 (Figure 5) will be'in engagement with the contact strips H3 and'll8.

Thus when the switch I2! is opened and the switches I29 and I30 are closed the motor'52 will be energized to rotate the Windlass drum 43 in a clockwise direction to wind the belt 4| thereon. This winding operation will continue until the switch elements are restored to normal position, the progressive tensioning of the shock cords 39 progressively moving the pulley 42 and lever 67 to the right'as viewed in Figure 3 until between the position of the lever El, and the," position of the lever 13 as determined by the wind velocity.

It will be apparent that thesprings 8i and 82 tend to hold the lever 73 in vertical position and these springs'are tensioned to provide whatever degree of movement of the lever 73 is desired between vertical position and maximum deflection in either direction; With the arrangement of the parts shown, the maximum deflection of .the lever 13 will'be relatively slight with a relatively substantial tensioning of the springs 81 and 82in which case sudden slight gusts of windwill not materially change the position of the disk 85. The piston HH and its bleed passage- |02 operating in the small cylinder Hi0 affords Y .a dashpot action to tend to prevent sudden movements of the disk 85 under the influence of sudden gusts of wind. The dashpot, however, will not have any effect on the positions of the parts under the. influence of steady wind pressures.

The switch element associated with the levers 6'! and 13 provide, in effect, a follow-up action of" the switch elementswith respect'to'ea'ch other upon movement out of normal position of either the plate H or the switch elements H or 18. The elements H1 and H8 may be ordinary contacts of low resistance instead of rheostat coils. The latter have been illustrated since, because of the resistance of these coils, slight deflection of the lever 13 will close the circuit through the motor 52 with substantial resistance therein so as to provide for slow operation of the motor. Such operation for slight deflections changes the tension of the shock cords 39 sufilciently rapidly. If a relatively heavy wind starts to blow increased deflection takes place and the switch element 18 willengage one or the other rheostat element plate ll turned in a counterclockwise direction about the pivot 12, whereupon thenut 10 may be tightened. This operation turns the plate I l and associated elements with respect to the switch contacts 1'! and 18 so as to provide the desired reduced tensioning of the shock cords 39. The adjustment may be made in the opposite direction if heavier loads are to be projected.

From the foregoing it will be apparent that the present apparatus provides for the generation of a force tending to move a catapault carriage at a given predetermined speed for a given load in the carriage in accordance with a predetermined approximate speed of operation of an airplane, and that it provides means functioning automatically to vary the loading of the force applying means in accordance with variations in the plane speed incident to the speed of the wind when the plane is flying in its pick-up position. The

device quickly variesthe loading of the shock cord for either a head wind or tail wind, and the variation in the loading of the shock cord occurs in direct proportion to the wind velocity to project the load quite accurately in accordance with the land speed of the airplane.

The term catapault in the appended claims is used in a general sense to indicate the structure inor on which is arranged the article to be projected and through. winch the force for projecting the article is directly transmitted to the article. As applied specifically to the disclosure of the present apparatus, the term catapult would define the carriage 22.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same and that various changes in the shape, size and arrangement of parts may be resorted to as do not depart from the spirit of the invention or the scope of the subjoined claims.

I claim:

1. An airplane pick-up mechanism comprising a catapult, .a source of power for operating the catapult to project an article therefrom to be picked. up by an airplane passing thereover at a known approximate air speed, and a control system for said source of power responsive to variations in wind velocity to increase the application of power from said source to said catapult in accordance with the velocity of a, tail wind blowing with respect to the pick-up plane whereby the article will be projected approximately at the land speed of the airplane.

2. An airplane'pick-up mechanism comprising a catapult, a source of power for operating the catapult to project an article therefrom to be picked up by an airplane passing thereover at a known approximate air speed, a control system for said power source to vary the application of power therefrom to the catapult, said system including a wind-responsive device, and means operatively connecting said wind-responsive device to said power sour'ceto control the latter to respectively increase and decrease the application of power to the catapult in accordance with the blowing of a tail wind or head wind with respect to the pick-up'plane whereby the article will be projected approximately at the land speed of the plane.

3. An airplane pick-up mechanism comprising a catapult, power means for applying a force ,tending'to move the catapult to project an article carried thereby, a latch normally holding said catapult against movement, means operative by a plane passing over the catapult in a given direction for releasing said latch, and means operable while said catapult is held by said latch for varying the force being applied by said power means to said catapult in accordance with wind direction and velocity whereby, when said latch is released, the article will be projected approximately at the land speedof the plane.

4. An airplane pick-up mechanism comprising a catapult, power means for applying a force tending tomove the catapult to project an article carried thereby, a latch normally holding said catapult against movement, means operative by a plane passing over the catapult in a given direction for releasing said latch, and means operable while said catapult is held by said latch for varying the force being applied by said power means to said catapult, and means responsive to wind direction and velocity for operating said last named means to increase or decrease the force of said power means in accordance with the direction and. velocity of the wind whereby, when said latch is released, the article will be projected approximately at the land speed of the airplane.

a. An airplane pick-up mechanism comprising a ,catapult, a source or power for operating the catapult to project an article therer'rom to be picked up by an airplane passing thereover at 'a known approximate air speed, a mechanism operatively connected to said power source and operable I01 determining the power generated by said source, a wind-responsive mechamsmhaving an element movable in a direction according to w nd direction and'to an extent proportional to wind velocity, and means inter-connecting said mechanisms to operate said mechanism operatively connected to said power source in accordance with operation of said element of said windresponsive mechanism whereby power Wlll be delivered from said source to said catapult to project the article at the approximate land speed of the airplane.

d. An airplane pick-up mechanism comprising a catapult, a source of power for operating the catapult to project an article therefrom to be" picked up byan airplane passing thereover at a known approximate air speed, a mechanism havmg mecnamcal connection with said power source i'or determining the power generated by said source, a second mechanism operable in a direccontrol mechanism interconnecting said mechanis'ms whereby the first named-mechanism will cause said source to develop power'proportional to the extent and direction of operation of said second mechanism, whereby said source will cause said catapult to project the article approximately at the-land speed of the airplane.

7. An airplane pick-up mechanism comprising acatapult, a tensionable source of power for operating the catapult, to project, an article therefrom to be picked up by an airplane passingthereover at a knownapproximate air speed, a mechanism connected to said powersource and operative for varying the tension of said power source, a second mechanism arrangedv to be wind deflectible in to project the article at a speed approximating opposite directions from. a normal position in' accordance with the direction .of the wind and to an extent proportional to the wind velocity, and means inter-connecting said. mechanisms for causing the first named mechanism to tension said power source in accordance with the direction and velocity of the wind .whereby the article will be projected by the catapult at a speed approximating the land speed of the airplane. 8. Apparatus constructed inv accordance with claim '7v wherein said means comprises a followa catapult adapted to hold an article to be projected, a loop connected to the article, means for supporting said loopin a position to be engaged by an airplane-carried pick-up element, a-source of power for operating the catapult, means for rendering said power source. effective for pro jecting the catapult upon the pulling of the loop by the airplane-carried element, and. means re sponsive to wind direction and velocity for controlling the speed at whichthecatapult will project the article whereby the latter .willibe projected at a speed approximating the land .speed of the airplane. a 7

10. An airplane -.pick-np mechanism comprising a catapult adapted to holdan article. to be projected, a loop connected to the articlameans for supporting said loop in.a..position to be --en-..

gaged by an airplane-carried pick-up element,

a source of power for operating the catapult;

means for rendering said power sourceeffective for projecting the catapult upon the pulling of the loop by the airplane-carried element, and means for varying the effective force appliedby said power source to said catapult, said means comprising a control device responsive to wind velocityand direction whereby. the force applied to the catapultwill project the article approx-imately at the land speed of the airplane. Y 11. An airplane pick-up mechanism comprising a catapult adapted to hold an article to be projected, a power source energizable to exert a force tending to operate. .said catapult alatch for holding said catapult against movement icy said .power source, means for releasing said-latch upon thepassageover the pick-up mechanism directions according to the direction of the wind and movable to an extent corresponding to wind that of. the land speed of the airplane.

12. Apparatus constructed in accordancewith claim 11 wherein said means comprises a follow up control mechanism having a pair of elements one of which is deflecti'ble in opposite directions from a normal position in accordancewith the deflection of said second mechanism, vand the other of which is constructedand arranged to follow up with respect. to the first mentioned element to control the operation of the first named mechanism. l

13. An airplane pick-up mechanism comprising a catapult adapted to hold an article to be projected, asource of power for exerting a force tending to operate said catapult, a latch. normally holding said catapult against movement, a loop connected to the article on the catapult, .means for supporting said loop in a position to be en-- gaged by. an airplane-carried pick-up element, means for releasing said latch upon the engage! ment of said pick-up element with said loop, a mechanism connected to said power source and operative for controlling energization of said source to determine the speed at which the article will be projected when said latch is released, a second mechanism movablein opposite directions from a normal :position in accordance with wind direction and to an extent proportionate to wind velocity, and means :for controlling the first named mechanism in accordance with the direction and extent of deflection of the second named mechanism whereby said source will operate said catapult to project the article at a speed approximating the land speed of the airplane. 1 a

14. Apparatus constructed in accordance with claim 13 wherein said last named means comprises a follow-up control mechanism responsive to deflection of said second mechanism and to operation of the first named mechanism whereby the latter causes energization of said power source in accordance with the direction and Velocity of the wind.

15. An airplane pick-up mechanism comprising a catapult adapted to hold an article to be projected, a tensionable device connected to the catapult to effect movement thereof, a latchnOrmally holding sai'dcatapult against movement,-

a reversible electric motor, means connected to and operated by said motor and connected to said tensionable means to determine the tensioning thereof, and means having connection J developed by said tensionable means to cause the article to be projected approximately at the land speed of the airplane when said latch is released. 7

16. Apparatus constructed in accordance with claim 15 wherein said last named meanscomprises an element defiectible in opposite directions from a normal position in accordance with the direction of the wind andxtoa'n extent-pro portionate to wind velocity, and a corrtrol 'mechanism for said motor :for energizing "the latter to increase or decrease the tension of said tensionable means in accordance with the position of said deflectible :member. a

Jorm x. Prams? 

